Question of the month

Not the mantid you thought it was…

I found this small insect in my garden. It looks like a preying mantid with clear wings. Can you tell me what it is?

Answer

Mantid Lacewing (Ditaxis biseriata). Photo by Kylie Ebrington Wasp mimicking mantispid (Euclimacia torquata)Austromantispa imbecilla emergent from the Bird-dropping Spider (Calaenia excavata) egg sac.The lovely insect you have found is a Mantid Lacewing (family Mantispidae) rather than a Preying Mantid, although they look very similar. Both have raptorial forelegs for catching and holding their prey, however Mantid Lacewings have transparent wings which fold over their bodies like a tent. Like other lacewings, the fore and hindwings of Mantid Lacewings are similar in shape and texture. The forewings of Preying Mantids are much narrower and leathery than the more delicate, fan-like wings of mantispids. Although the raptorial forelimbs of mantispids and true mantids are similar, they evolved independently (a phenomenon called ‘convergent evolution).

48 species of Mantispidae are currently known to occur in Australia. One interesting species, Euclimacia torquata, looks very much like a wasp. Mimicking a dangerous wasp presumably gives these mantispids some protection from predators.

Not much is known about the early life stages of these insects, except for those in the subfamily Mantispinae. Females of this subfamily lay batches of hundreds of eggs. When the larvae hatch they seek out spider egg sacs and feed on the eggs. The larvae of some species of Mantid Lacewings also ‘board’ spiders, living on them until they mate or lay eggs. The larvae have jaws modified for piercing and sucking out the contents of the eggs. Each larva eventually makes a cocoon and pupates inside the spider egg sac. The size of adult mantid lacewings in this subfamily varies greatly, possibly due to the availability of food for the larvae.

Queensland Museum's Find out about... is proudly supported by the Thyne Reid Foundation and the Tim Fairfax Family Foundation.